JP6716805B2 - Screen system - Google Patents

Description

The present invention relates to a screen system including a contaminant removing screen device that captures contaminants by a screen member and removes the captured contaminants.

There is known a screen device that removes contaminants from received water such as sewage containing contaminants (see, for example, Patent Documents 1 and 2). In this screen device, contaminants captured without being able to pass through the interval between the screen members provided at intervals connecting the upstream side and the downstream side, by performing a transfer drive for transferring on the upstream side of the screen member, Remove the contaminants. The contaminants captured by the screen member are captured so as to close the space between the screen members.

JP-A-53-132149 JP, 2004-183443, A

However, with the above-described screen device, it is not possible to remove impurities that have passed through the space between the screen members. Therefore, it is conceivable to reduce the interval between the screen members to improve the removal rate of foreign substances. Will have to be made larger than necessary. In addition, particularly a string-like object is likely to pass through even if the above interval is narrowed.

In view of the above circumstances, it is an object of the present invention to provide a screen system including a contaminant removing screen device capable of removing contaminants that would otherwise pass through the space between the screen members.

The screen system of the present invention which solves the above object,
The upstream and busy tool夾 matters the distance on the upstream side of the screen member with a gap that connects the downstream side can not pass through the spacing between the screen member provided in the water tank at the upstream side of the screen member A contaminant removal screen device for removing the contaminants by performing a transfer drive for transferring;
A pump that supplies sewage containing the contaminants to the aquarium;
In the water tank, a water level sensor for detecting the water level on the upstream side of the screen member,
A control means for controlling the contaminant removal screen device,
The contaminant removal screen device includes a pair of fixed screen members and an operating screen member that is provided between the pair of fixed screen members and moves with respect to the fixed screen members, and the operating screen members move. By doing so, the contaminants are transferred stepwise along the longitudinal direction of the fixed screen member,
The screen member is for gradually capturing the contaminants that may pass through the gaps by gradually closing the gaps with the contaminants,
The control means detects that the space is too blocked by the contaminants when the water level detected by the water level sensor reaches a driving water level, and starts the transfer drive only in response to the detection. It is characterized by being a thing.

further,
The fixed screen member is provided with a plurality of fixed step portions along the longitudinal direction,
The operating screen member is provided with a plurality of operating step portions along the longitudinal direction,
The foreign matter removal screen device, the foreign matter caught on the operating step portion, by moving the operating screen member upward and upstream side, transferred to the fixed step portion above the operating step portion, Then, the operation screen member may be repeatedly driven for one cycle in which the operation screen member returns downward and to the downstream side.

According to the present invention, it is possible to provide a screen system provided with a contaminant removing screen device capable of removing contaminants that would otherwise pass through the space between the screen members.

It is a figure which shows typically some facilities in a sewage treatment plant. It is a front view of the screen system for raw sludge corresponding to one embodiment of the present invention. FIG. 3 is a plan view of the raw sludge screen unit shown in FIG. 2. It is a figure which shows the detail of the overflow unit for drainage. (A) is the schematic diagram which looked at the screen member provided in the foreign matter removal screen device from the upstream side of the water tank, and (b) shows the state in which the foreign matter removal screen device 22 removes foreign substances. It is a figure which shows in steps from. It is a flowchart which shows the flow of the foreign material removal process which the control means of the raw sludge screen system performs.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram schematically showing a part of the facilities in the sewage treatment plant.

In FIG. 1, a settling tank 10, a raw sludge screen unit 20, a scum pit 30, and a scum screen unit 40 are shown.

The settling basin 10 shown in FIG. 1 receives sewage such as sewage and rainwater from one end side in the longitudinal direction (left side in FIG. 1), causes sludge contained in the received sewage to settle on the basin 1d, and the other end side (FIG. Then drain from the right side). Hereinafter, the left direction in FIG. 1 is referred to as the upstream, and the right direction in FIG. 1 is referred to as the downstream. A sludge pit 11 is provided in the bottom 1d of the sedimentation basin 10 on the upstream side, and a drain gutter 12 is installed near the water surface on the downstream side. In the settling basin 10, the sludge settling on the bottom 1d of the basin is collected in a sludge pit 11 by a sludge attractor (not shown). The sludge collected in the sludge pit 11 is sent by the sludge pump 111 to the raw sludge screen unit 20 installed outside the sedimentation basin 1. The sludge collected in the sludge pit 11 contains impurities such as dust that sinks in the water. Hereinafter, the sewage containing sludge sent from the sludge pit 11 to the raw sludge screen unit 20 is referred to as raw sludge. As will be described later in detail, the raw sludge screen unit 20 is a unit that removes impurities contained in the raw sludge, and the raw sludge from which the impurities have been removed by the raw sludge screen unit 20 is After that, it is sent to the sludge concentration treatment facility and the sludge dewatering treatment facility. In the settling basin 10, scum floating near the water surface W1 is scraped up to the drain gutter 12 by a scum scraper (not shown). The drain gutter 12 is connected to the scum pit 30, and the sewage (scum water) containing scum is collected in the scum pit 30, and then the scum screen installed from the scum pit 30 by the scum pump 301 to the outside of the sedimentation basin 1. It is sent to the unit 40. The scum water collected in the scum pit 30 contains impurities such as dust floating on the water. The scum screen unit 40 is a unit for removing scum, which is a contaminant contained in scum water, and the water from which the scum is removed by the scum screen unit 40 is returned to the sewage treatment plant. ..

Next, the raw sludge screen unit 20 will be described as an example, but the same applies to the scum screen unit 40.

FIG. 2 is a front view of a raw sludge screen system according to an embodiment of the present invention.

The raw sludge screen system 2 shown in FIG. 2 is provided with the raw sludge screen unit 20 and the control means 50 shown in FIG.

FIG. 3 is a plan view of the raw sludge screen unit shown in FIG. This plan view corresponds to a view of the raw sludge screen unit 20 as viewed from above.

The raw sludge screen unit 20 shown in FIGS. 2 and 3 includes a water tank 21, a contaminant removing screen device 22, and a water level sensor 23. The raw sludge screen unit 20 shown in FIG. 2 and FIG. 3 receives the raw sludge from the left side of the figure (see the thick arrow in the figure). Hereinafter, the left side in FIGS. 2 and 3 is referred to as the upstream, and the right side is referred to as the downstream. Further, the direction perpendicular to the paper surface in FIG. 2 and the vertical direction in FIG. 3 may be referred to as the width direction.

In the lower half of the side wall on the upstream side of the water tank 21 shown in FIG. 2, an inclined portion 211 that is inclined toward the bottom toward the bottom 21a is provided, and in the lower half of the side wall on the downstream side, the bottom 21a is provided. The inclined portion 212 is provided so as to incline toward the upstream side. Therefore, the water tank 21 has a shape in which the bottom portion 21a side is narrowed. Three water levels are set in this aquarium 21. The lowest water level is the reference water level L1, the highest water level is the emergency water level L3, and the water level higher than the reference water level L1 by a predetermined length (here, 200 mm to 300 mm) is the driving water level L2.

The raw sludge screen unit 20 is provided with an emergency overflow unit 24 on the upstream side and a drainage overflow unit 25 on the downstream side. That is, an emergency overflow unit 24 is provided on the upstream side of a screen member provided on a contaminant removal screen device 22 described later in detail, and a drainage overflow unit 25 is provided on the downstream side. Both the emergency overflow unit 24 and the drainage overflow unit 25 have drainage basins 241 and 251. As shown in FIG. 3, both drainage basins 241 and 251 are provided so as to project in the width direction of the water tank 21. By opening the canopies 242 and 252, it is possible to look inside. Further, as shown in FIG. 2, the drainage overflow unit 25 has a drainage dam plate 253. The height position of the upper end of the drainage dam plate 253 is slightly lower than the reference water level L1. The sludge collected in the sludge pit 11 is sent to the water tank 21 by driving the sludge pump 111, and the water level of the water tank 21 rises. The drive control of the sludge pump 111 is performed by the control means 50 included in the raw sludge screen system 2. The water level sensor 23 is installed above the emergency water level L3, is an infrared sensor that detects the water level of the water tank 21 using infrared rays, and the detection result is sent to the control means 50. In FIG. 2, the signal line is represented by a dotted line. The water level sensor 23 may be installed on the bottom portion 21a instead of the water pressure sensor that detects water pressure. The control means 50 continuously drives the sludge pump 111 until the water level sensor 23 detects that the driving water level 21 has been reached. The sludge pump 111 may be stopped when the detection result of the water level sensor 23 does not change even after a lapse of a predetermined time or when the sludge attractor installed in the settling tank 10 is stopped.

FIG. 4 is a diagram showing details of the drainage overflow unit, FIG. 4A is a schematic view of the drainage overflow unit when viewed from above, and FIG. ) Is a view when seen from the B direction, (c) is a cross-sectional view taken along the line CC' of (a), and (d) is D of (a). It is a -D' sectional view.

In FIG. 4A, the left side of the drawing is the upstream side of the water tank 21, and the right side is the downstream side of the water tank 21. In FIG. 4A, the side wall 213 of the water tank 21 is shown. The side wall 213 is a wall connecting the upstream side and the downstream side of the water tank 21. The side wall 213 is provided with a rectangular opening 213a, and the drainage box 252 is attached to an edge portion defining the opening 213a. The drainage dam plate 253 is provided at the boundary between the inside of the water tank 21 and the inside of the drainage box 252. Both ends of the drainage dam plate 253 are inserted between the side wall 213 and the holding plate 214, and the drainage dam plate 253 is installed below the boundary portion. The inside of the water tank 21 and the inside of the drainage basin 252 are connected at a portion above the drainage weir plate 253, and are not connected at a portion below the drainage weir plate 253. In FIG. 4A, the upper side of the drainage weir plate 253 is the water tank 21 side, and the lower side of the drainage weir plate 253 is the drainage box 252 side. In FIG. 4B, the water tank 21 side is on the back side of the drainage dam plate 253, and the drainage box 252 side is on the paper face side of the drainage dam plate 253. In FIGS. 4C and 4D, the left side of the drainage weir plate 253 is the water tank 21 side, and the right side of the drainage weir plate 253 is the drainage trough 252 side.

When the water level of the water tank 21 exceeds the height position of the upper end of the drainage weir plate 253, the water in the water tank 21 flows over the drainage weir plate 253 and flows into the drainage box 252. A state in which the water in the water tank 21 flows over the drainage dam plate 253 and flows into the drainage basin 252 is represented by a curved arrow in FIG. 4A, and is also represented in FIG. 4C and FIG. .. The water in the water tank 21 referred to here is raw sludge that has passed through the screen member provided in the contaminant removal screen device 22, that is, sewage containing sludge from which contaminants have been removed by the contaminant removal screen device 22. The sewage is sent to a sludge concentration treatment facility and a sludge dewatering treatment facility, which are facilities for the post-treatment process. In this way, the raw sludge that has passed through the screen member provided in the contaminant removing screen device 22 is drained to the outside of the raw sludge screen unit 20 by the drainage overflow unit 25.

The structure of the emergency overflow unit 24 is also the same as the structure of the drainage overflow unit 25 described with reference to FIG. 4, but the emergency overflow unit 24 is provided at a position higher than the drainage overflow unit 25. Further, as shown in FIG. 2, the emergency overflow unit 24 has an emergency barrier plate 243. The height position of the upper end of the emergency barrier plate 243 is slightly lower than the emergency water level L3. Therefore, when the water level in the water tank 21 reaches the emergency water level L3, the water in the water tank 21 flows over the emergency weir plate 243 and flows into the drainage box 242 of the emergency overflow unit 24. The raw sludge in the water tank 21 referred to here is the raw sludge before passing through the screen member provided in the contaminant removal screen device 22, that is, the sludge before the contaminants are removed by the contaminant removal screen device 22. The sewage contained is returned to the upstream end of the contaminant removal screen device 22. As described above, when the emergency water level L3 is exceeded, the raw sludge in the water tank 21 is temporarily discharged to the outside of the raw sludge screen unit 20 by the emergency overflow unit 24. The case where the water level in the water tank 21 exceeds the emergency water level L3 may be the case where the contaminant removing screen device 22 has failed. In addition, in a confluence type facility that treats rainwater and sewage collectively, when heavy rain falls, or when a large amount of fallen leaves flow in autumn, etc.

Subsequently, the contaminant removing screen device 22 will be described in detail. As shown in FIG. 2, the contaminant removing screen device 22 includes a screen member 220, a chain drive mechanism 225, and a chute 227. The chain drive mechanism 225 is driven by the rotation of the transfer motor 225m. The rotation control of the transfer motor 225m is performed by the control means 50.

The screen member 220 is arranged in the water tank 21 in an inclined posture such that the lower portion is located on the upstream side of the water tank 21 and the upper portion is located on the downstream side. The upper portion of the screen member 220 is provided above the emergency water level L3.

FIG. 5A is a schematic view of the screen member provided in the contaminant removing screen device as viewed from the upstream side of the water tank. The screen member 220 shown in FIG. 2 has a plurality of sets of a pair of long fixed screen members 221 and a similar long operating screen member 222 provided between the pair of fixed screen members 221. That is, in the contaminant removing screen device 22, the fixed screen member 221 and the operating screen member 222 are alternately arranged with a predetermined interval W (for example, 2 mm or more and 6 mm or less) over the entire width of the water tank 21. In addition, in FIG. 5A, the screen member 220 at the central portion in the width direction is omitted to simplify the drawing. The predetermined interval W is an interval connecting the upstream side and the downstream side, which is set from the balance between the flow rate of the raw sludge passing through the contaminant removal screen device 22 and the size of the device. Among the impurities contained in the raw sludge, the impurities that cannot pass through the predetermined distance W are captured by the screen member so as to close the predetermined distance W on the upstream side of the screen member.

A plurality of fixed step portions 2211 are provided along the longitudinal direction on the upstream side of the fixed screen member 221. Further, a plurality of operating step portions 2221 are provided on the upstream side of the operating screen member 222 along the longitudinal direction. That is, in both the fixed screen member 221 and the operating screen member 222, stepwise steps are continuously provided along the longitudinal direction on the upstream side.

Next, the removal of contaminants by the contaminant removal screen device 22 will be described. FIG.5(b) is a figure which shows a mode that the foreign material removal screen apparatus 22 removes foreign materials in steps from a width direction. In FIG. 5B, the raw sludge flows in from the left side of the figure and flows toward the right side. Therefore, the left side of the figure is the upstream side, and the right side is the downstream side.

FIG. 5B shows the operation screen member 222 at the initial position in (A). The lower portion of the fixed screen member 221 is in contact with the bottom portion 21a of the water tank 21, and the operating screen member 222 at the initial position is at the same height position as the fixed screen member 221, and when viewed from the width direction, the two overlap. There is. Therefore, the lower portion of the operating screen member 222 at the initial position is also in contact with the bottom portion 21a of the water tank 21. Further, the foreign matter X is caught from the operation step portion 2221 which is the fifth step from the bottom of the operation screen member 222 shown in (A) to the fixed step portion 2211 which is also the fifth step from the bottom of the adjacent fixed screen member 221. There is. The height position of the operating step portion 2221 which is the fifth step from the bottom of the operating screen member 222 shown in (a) is the same as the height position of the fixed step portion 2211 which is the fifth step from the bottom of the fixed screen member 221. I am doing it.

The operation screen member 222 moves with respect to the fixed screen member 221 by driving the chain drive mechanism 225 shown in FIG. The operating screen member 222 shown in (a) is moved upward and upstream with respect to the fixed screen member 221, and the operating screen member 222 shown in (c) is just one step above the fixed screen member 221. In the state in which the sludge is moved to, the fixed screen member 221 overlaps in the flow direction of the raw sludge. That is, the height position of the operating step portion 2221 which is the fifth step from the bottom of the operating screen member 222 shown in (c) is the same as the height position of the fixed step portion 2211 which is the sixth step from the bottom of the fixed screen member 221. They match each other, and the foreign matter X is raised by one step by the operating screen member 222 and hooked on the fixed step portion 2211 which is the sixth step from the bottom of the fixed screen member 221. In this way, the foreign matter X caught on the fifth operation step portion 2221 is moved to the downstream side in the moving direction of the operation screen member 222 with respect to the fifth operation step element 2221 by the movement of the operation screen member 222. Is transferred to the sixth fixed step portion 2211. The movement operation of the operation screen member 222 from (A) to (C) shown in FIG. 5B corresponds to the transfer drive.

The operating screen member 222 shown in (D) is below and downstream of the operating screen member 222 shown in (C), with the foreign matter X left in the fixed step portion 2211 that is the sixth step from the bottom of the fixed screen member 221. The operation screen member 222 shown in (e) returns to the same height position as the fixed screen member 221, and when viewed from the width direction, the two overlap. That is, the operation screen member 222 shown in (e) has returned to the initial position. The movement operation of the operation screen member 222 from (c) to (e) shown in FIG. 5B corresponds to the return operation. One cycle of driving such as transfer driving and returning operation of the operation screen member 222 is completed by the chain member of the chain driving mechanism 225 shown in FIG.

As described above, the foreign matter X is transferred one step above the fixed step portion 2211, and finally reaches the uppermost fixed step portion 2211 of the fixed screen member 221. That is, the foreign matter X is transferred stepwise along the longitudinal direction of the fixed screen member 221. The uppermost fixed step portion 2211 is located above the water surface (emergency water level L3), and the contaminants that have reached the uppermost fixed step portion 2211 are stored in the chute 227 shown in FIG. Transported to the input port. The chute 227 has a discharge port 2271 opened to the outside of the foreign matter removal screen device 22, and the foreign matter conveyed to the input port of the chute 227 is discharged to the outside of the foreign matter removal screen device 22 from the discharge port 2271. It

In the present embodiment, the operating screen member 222 is moved by driving the chain drive mechanism 225, but the operating screen member 222 is moved by moving the frame without the chain to which the operating screen member 222 is attached. May be moved.

Next, the control means 50 of the raw sludge screen system 2 shown in FIG. 2 will be described.

FIG. 6 is a flowchart showing the flow of the foreign matter removing process executed by the control means of the raw sludge screen system.

First, the sludge pump 111 is driven while the transfer motor 225m that drives the chain drive mechanism 225 is stopped (step S11). By doing so, the sludge collected in the sludge pit 11 is sent to the water tank 21 as raw sludge, and the raw sludge flows into the contaminant removal screen device 22. By executing this step S11, the receiving step according to the present invention is executed.

Next, it is determined whether or not the water level of the water tank 21 has reached the drive water level L2 provided between the reference water level L1 and the emergency water level L3, based on the detection result of the water level sensor 23 (step S12), and the drive water level. The process of step S12 is repeatedly executed until L2 is reached, and the driving of the sludge pump 111 is continued. Even in the step S12, the transfer motor 225m is in a stopped state, and the operation screen member 222 does not perform the transfer drive. As a result, the gap between the fixed screen member 221 and the operating screen member 222 is gradually blocked by the contaminants, and the gap is narrowed by the contaminants, and even if the contaminants that would otherwise pass through pass through. Can't do it. That is, it is repeated that the next foreign matter is caught by the foreign matter caught in the interval of the screen member 220. The sludge itself, which does not include foreign matters, is a granular matter, and thus can originally pass through the predetermined interval W shown in FIG. 5A. Further, the sewage itself can also pass through the predetermined interval W. However, if the distance between the fixed screen member 221 and the operating screen member 222 is narrowed by contaminants, the flow rate of the sewage itself passing through the screen member 220 per unit time is reduced, or even the sludge itself which can originally pass through. Even if the waste cannot pass through the screen member 220 and drainage is performed by the drainage overflow unit 25, the water level of the water tank 21 gradually rises. In other words, the fact that the water level is rising while the transfer motor 225m is stopped and the sludge pump 111 is being driven means that even foreign substances that would normally pass through the space between the screen members 220 are included. , Is evidence that it has been captured by the screen member 220. By executing this step S12, the monitoring step according to the present invention is executed.

When the water level in the water tank 21 reaches the driving water level L2, the transfer motor 225m starts rotating (step S13), and the operation screen member 222 starts one cycle of drive such as transfer drive and return operation. Here, the transfer drive is performed for the first time.

Then, it is determined whether the water level in the water tank 21 has not reached the emergency water level L3 based on the detection result of the water level sensor 23, and if it has not reached the emergency water level L3, the process proceeds to step S15. On the other hand, if the emergency water level L3 has been reached, the sludge pump 111 is stopped (step S16), and the process proceeds to step S15.

In step S15, it is determined whether or not the water level in the water tank 21 has returned to the reference water level L1, based on the detection result of the water level sensor 23, and the processes in the previous step S14 and this step S15 are performed until the water level returns to the reference water level L1. Is repeatedly executed, and the rotation of the transfer motor 225m continues. As a result, the transfer drive by the operating screen member 222 is repeatedly performed until the water level in the water tank 21 returns to the reference water level L1. In this embodiment, one cycle of driving of the operating screen member 222 is repeated ten or more times per minute.

The transfer driving by the operating screen member 222 is repeatedly performed, so that the contaminants caught in the space between the screen members 220 are removed. As a result, the interval between the screen members 220 returns to the predetermined interval W shown in FIG. 5A, and the flow rate of the sewage itself passing through the screen member 220 increases to the original flow rate. Further, the sludge itself can pass through the screen member 220. Drainage is continued in the drainage overflow unit 25, and the water level in the water tank 21 drops to the reference water level L1. According to an experiment by the present inventor, the water level in the water tank 21 drops to the reference water level L1 in about 20 to 30 seconds. By carrying out step S13, the transfer step referred to in the present invention is carried out.

The water level in the water tank 21 should drop to the reference water level L1 in about 20 to 30 seconds, but if the contaminant removal screen device 22 fails and the transfer drive is not performed, or if the rainwater and sewage are collected together. In a confluence type facility that treats with water, when there is heavy rain, or when a large amount of fallen leaves flow in in the fall, the water level that should have dropped to the standard water level L1 may reach the emergency water level L3. is there. Therefore, the water level monitoring process in step S14 is performed, and when the emergency water level L3 is reached, the sludge pump 111 is stopped in step S16. When the sludge pump 111 is stopped, the raw sludge is not sent into the water tank 21, and the further rise of the water level in the water tank 21 is suppressed, and the raw sludge overflows from the water tank 21 by the drainage in the emergency overflow unit 24. Is prevented.

When the water level in the water tank 21 reaches the reference water level L1, the rotation of the transfer motor 225m is stopped (step S17), and the operation screen member 222 is stopped. By executing this step S17, the stopping step according to the present invention is executed. When the execution of the process of step S17 is completed, the process returns to step S12.

By repeating step S13 and step S17, it becomes possible to repeatedly remove even foreign matters that would otherwise pass through the space between the screen members 220. Further, the longer the time interval between step S17 and step S12 is, the more the driving energy of the transfer motor 225m can be saved.

In the above description, the raw sludge screen unit 20 is described as an example, but the present invention is not limited to sewage treatment facilities, but may be applied to facilities that treat water such as industrial water and agricultural water. it can. Further, in the above description, the transfer drive is a drive for transferring contaminants in stages, but may be a drive for continuous transfer (for example, drive by a belt conveyor).

In the above description,
A transfer drive for transferring, on the upstream side of the screen member, a contaminant that cannot pass through the interval of the screen member provided at a distance connecting the upstream side and the downstream side and closes the interval on the upstream side of the screen member. In the method for operating the contaminant removal screen device for removing the contaminants by performing:
A receiving step of receiving water with the transfer drive stopped,
A monitoring step for monitoring the water level during execution of the receiving step,
A transfer step of starting the transfer drive when the water level being monitored reaches a drive water level higher than a reference water level and transferring the contaminants;
And a stop step of stopping the transfer drive when the water level being monitored returns to the reference water level, the operating method of the foreign matter removing screen device.
I explained.

According to the operating method of the contaminant removing screen device, the transfer drive is not performed until the driving water level is reached. Then, the interval between the screen members is gradually closed by the contaminants, the interval is narrowed by the contaminants, and even the contaminants that would otherwise pass cannot pass through. That is, it is repeated that the next foreign matter is caught on the foreign matter caught in the interval of the screen member. When this happens, the flow rate of the incoming water passing through the screen device decreases, the water level gradually rises, and eventually reaches the driving water level. Here, for the first time, the transfer drive is performed to remove impurities trapped in the space between the screen members, the flow rate of the incoming water passing through the screen device is increased to the original flow rate, and the water level is lowered to the reference water level. Thus, by repeating the transfer step and the stop step, it becomes possible to repeatedly remove the contaminants that would otherwise pass through the space between the screen members. Further, the longer the time interval between the stopping step and the transferring step is, the more the driving energy of the contaminant removing screen device can be saved.

The operation method of the above-mentioned contaminant removal screen device can be applied not only to a sewage treatment facility but also to a facility for treating water such as industrial water and agricultural water. Further, the transfer drive may be a drive for transferring contaminants in a stepwise manner, or may be a drive for continuously transferring contaminants (for example, drive by a belt conveyor).

In the method for operating a contaminant removing screen device, the transferring step may be a step of transferring the contaminants by moving an operating screen member provided between the pair of fixed screen members.

Further, in the method for operating a contaminant removing screen device, the transferring step may be a step of transferring the contaminants in stages along the longitudinal direction of the fixed screen member.

Also, in the above description,
Water level monitoring means for monitoring the water level in the aquarium,
A screen member provided at a distance connecting the upstream side and the downstream side of the water tank, which cannot pass through the space and closes the space on the upstream side of the screen member, is transferred on the upstream side of the screen member. A contaminant removal screen device for removing the contaminants by performing transfer driving,
A control means for controlling the transfer drive of the contaminant removal screen device,
The control means starts the transfer drive when the water level monitored by the water level monitoring means reaches a driving water level higher than a reference water level, and the water level monitored by the water level monitoring means returns to the reference water level. Then, the screen system is characterized in that the transfer drive is stopped.
Was also explained.

According to this screen system, it is possible to carry out the method of operating the above-mentioned contaminant removal screen device, and it is also possible to remove contaminants that would otherwise pass through the space between the screen members.

The water level monitoring means may monitor the water level in a water tank provided with a drain outlet downstream of the contaminant removal screen device.

In the screen system, the contaminant removing screen device includes a pair of fixed screen members and an operating screen member that is provided between the pair of fixed screen members and moves with respect to the fixed screen members. The contaminants may be transferred by moving the operation screen member.

Further, in the screen system, the fixed screen member is provided with a plurality of fixed step portions along the longitudinal direction,
The operating screen member is provided with a plurality of operating step portions along the longitudinal direction,
The foreign matter removal screen device, by moving the foreign matter caught on the operating step portion, the operating screen member, to the fixed step portion downstream of the operating step portion in the moving direction of the operating screen member. It may be transferred.

Also, in the above description,
A transfer drive for transferring, on the upstream side of the screen member, a contaminant that cannot pass through the interval of the screen member provided at a distance connecting the upstream side and the downstream side and closes the interval on the upstream side of the screen member. In the method for operating the contaminant removal screen device for removing the contaminants by performing:
A receiving step in which the water containing the contaminants is received in a state where the transfer drive is stopped, the received water is allowed to pass through the interval, and the interval is gradually closed by the contaminants that cannot pass through the interval;
A monitoring step for monitoring the water level during execution of the receiving step,
When the water level being monitored reaches a drive water level higher than a predetermined reference water level located above the lower end of the screen member, the transfer drive is started, and a transfer step of transferring the contaminants,
And a stop step of stopping the transfer drive when the water level being monitored returns to the reference water level, the operating method of the foreign matter removing screen device.
Was also explained.

Furthermore, in the above description,
Water level monitoring means for monitoring the water level in the aquarium,
A screen member provided at a distance connecting the upstream side and the downstream side of the water tank, which cannot pass through the space and closes the space on the upstream side of the screen member, is transferred on the upstream side of the screen member. A contaminant removal screen device for removing the contaminants by performing transfer driving,
A control means for controlling the transfer drive of the contaminant removal screen device,
The control means stops the transfer drive, and while the received water passes through the interval, while monitoring the water level monitoring means in a state where the interval is gradually blocked by the impurities that cannot pass through the interval. When the water level reaches a driving water level higher than a predetermined reference water level located above the lower end of the screen member, the transfer drive is started, and the water level being monitored by the water level monitoring means is the reference water level. The screen system, wherein the transfer drive is stopped when the screen is returned to.
Was also explained.
Furthermore, in the above description,
A transfer for transferring, on the upstream side of the screen member, a contaminant that cannot pass through the space of the screen member provided with a space connecting the upstream side and the downstream side of the water tank and closes the space on the upstream side of the screen member A foreign matter removing screen device for removing the foreign matter by driving.
In the water tank, a water level sensor for detecting the water level on the upstream side of the screen member,
A control means for controlling the contaminant removal screen device,
The contaminant removal screen device includes a pair of fixed screen members and an operating screen member that is provided between the pair of fixed screen members and moves with respect to the fixed screen members, and the operating screen members move. By doing so, the contaminants are transferred stepwise along the longitudinal direction of the fixed screen member,
The screen system is also described in which the control means controls the transfer drive according to the water level detected by the water level sensor.
Also,
The control means may start the transfer drive when the water level detected by the water level sensor reaches a driving water level.
Furthermore, in the above description,
On the upstream side of the screen member that cannot pass through the interval of the screen member provided at a distance that connects the upstream side and the downstream side of the water tank to which the raw sludge containing foreign substances collected in the sedimentation tank is supplied. A contaminant removal screen device for removing the contaminants by performing a transfer drive for transporting the contaminants that close the space on the upstream side of the screen member,
In the water tank, a water level sensor for detecting the water level on the upstream side of the screen member,
A control means for controlling the contaminant removal screen device,
The contaminant removal screen device includes a pair of fixed screen members and an operating screen member that is provided between the pair of fixed screen members and moves with respect to the fixed screen members, and the operating screen members move. Thus, the contaminants are transferred stepwise along the longitudinal direction of the fixed screen member,
The screen system is also described in which the control means controls the transfer drive according to the water level detected by the water level sensor.
Also,
The screen member is for gradually capturing the contaminants that may pass through the gaps by gradually closing the gaps with the contaminants,
The control means detects that the space is too blocked by the contaminants when the water level detected by the water level sensor reaches a driving water level, and starts the transfer drive in response to the detection. May be

111 Sludge Pump 2 Screen System for Raw Sludge 20 Screen Unit for Raw Sludge 21 Water Tank 22 Contaminant Removal Screen Device 220 Screen Member 221 Fixed Screen Member 2211 Fixed Step 222 Operation Screen Member 2221 Operation Step 225 Chain Drive Mechanism 225m Transfer Motor 227 Chute 23 Water level sensor 24 Emergency overflow unit 25 Drain overflow unit 251 Drainage box 253 Drain weir plate 50 Control means L1 Standard water level L2 Driving water level L3 Emergency water level X Foreign matter

Claims (2)

The upstream and busy tool夾 matters the distance on the upstream side of the screen member with a gap that connects the downstream side can not pass through the spacing between the screen member provided in the water tank at the upstream side of the screen member A contaminant removal screen device for removing the contaminants by performing a transfer drive for transferring;
A pump that supplies sewage containing the contaminants to the aquarium;
In the water tank, a water level sensor for detecting the water level on the upstream side of the screen member,
A control means for controlling the contaminant removal screen device,
The contaminant removal screen device includes a pair of fixed screen members and an operating screen member that is provided between the pair of fixed screen members and moves with respect to the fixed screen members, and the operating screen members move. By doing so, the contaminants are transferred stepwise along the longitudinal direction of the fixed screen member,
The screen member is for gradually capturing the contaminants that may pass through the gaps by gradually closing the gaps with the contaminants,
The control means detects that the space is too blocked by the contaminants when the water level detected by the water level sensor reaches a driving water level, and starts the transfer drive only in response to the detection. A screen system characterized by being a thing. The fixed screen member is provided with a plurality of fixed step portions along the longitudinal direction,
The operating screen member is provided with a plurality of operating step portions along the longitudinal direction,
The foreign matter removal screen device, the foreign matter caught on the operating step portion, by moving the operating screen member upward and upstream, to transfer to the fixed step portion above the operating step portion, Next, the screen system according to claim 1, wherein the operation screen member is returned downward and to the downstream side, and the operation screen member is repeatedly driven for one cycle.